Microsurgical microscope system

ABSTRACT

The microsurgical microscope system with a stand and with a parallelogram linkage is characterized in that a bar, which connects two substantially horizontal bars and to which the microscope is connected, also has a receiving device connected to it for accessory parts of the microscope and/or additional weights.

BACKGROUND OF THE INVENTION

The invention relates to a microsurgical microscope system with a standand with a microscope arranged thereon, in which system the stand has abase part and a substantially horizontal parallelogram linkage with twosubstantially horizontal bars and first and second further barsconnecting the horizontal bars, of which the first further bar isconnected to a mounting device for the microscope.

For operations on fine biological structures, in particular forneurosurgical operations on the brain and spinal cord, but also in theENT field, operating microscopes are used which are arranged on easilymovable stands near the operating site.

Depending on the type of operation, operating microscopes and stands ofdifferent size and design are used. In neurosurgery, systems have provenparticularly useful in which the stand has weights which, in the mannerof a balance, compensate the weight of the operating microscope.However, since the microscope has to be moved in the three spatialdirections, the stand must have at least three axes of movement. Whileone axis can be arranged vertically and for this reason no weightcompensation has to take place around this axis, it is necessary toeffect the balance about two axes by changing the weights or moving theweights.

A great many examples of such stands can be found in the patentliterature. In particular, U.S. Pat. No. 5,528,417 describes a system inwhich the microscope weight is compensated by a counterweight which ismoved along a curve depending on the weight of the microscope. In thissystem, the holder for the microscope is additionally held horizontallyby connecting bars, so that the microscope is always suspendedvertically under the holder.

Depending on the operation, different additional parts are needed on theoperating microscope, and these alter the weight of the operatingmicroscope. For this reason, the system has to be balanced again afterthe microscope has been re-equipped.

However, regularly required weight compensation has disadvantages. Forcompensating the shift in weight, the range of compensation is limitedand has to be widened by arranging additional weights on the stand, ifnecessary. In the case of automatic balancing, a high level ofelectromechanical expenditure is necessary, which considerably increasesthe costs of a system. If it is forgotten to carry out the balancingprocedure, the result is inconvenience for the surgeon or even a dangerto the patient through uncontrolled movements of the microscope.

For these reasons, the microscopes are equipped with all possibleaccessory parts, even if these are not required for an operation. Inthis way it is possible to dispense with a balancing procedure beforethe operation and thus avoid the associated risk of imbalance. Thedisadvantage, however, is that the microscope is made large and unwieldyby the many accessory parts and greatly obstructs the view of theoperating site.

The invention starts out from a microscope system of the type mentionedin the introduction (U.S. Pat. No. 5,528,417). The object of theinvention is to make available a microscope system in which accessoryparts can be arranged on and removed from the microscope without theneed for renewed balancing.

SUMMARY OF THE INVENTION

The solution according to the invention lies in the fact that the firstfurther bar also has a receiving device connected to it for accessoryparts of the microscope and/or additional weights.

The invention makes use of the knowledge that in this microscope systemthe balancing does not change if the weight acting on the parallelogramlinkage does not change. This weight does not change, however, if partsof the microscope, which is connected to the first further bar of theparallelogram linkage, are removed and are arranged in or on thereceiving device for the accessory parts, which is likewise connected tothe first further bar of the parallelogram linkage. The fact that thedistance of these objects from other parts of the stand or any of thehinges of the parallelogram linkage changes, which change would causedifferent rotational moments, surprisingly is not important here. Thisis due to the fact that, even upon swiveling of the parallelogramlinkage, the orientation of the first further bar of the parallelogramlinkage and of the microscope and accessory parts arranged thereon doesnot change.

Accessory parts which are not required at a given time do not thereforeimpede the work with the microscope because they can be removed from themicroscope and can be arranged in or on the receiving device foraccessory parts, where they no longer obstruct the work with themicroscope. The corresponding parts do not have to be carried throughthe operating theatre and in particular taken to other rooms, whichwould entail the risk of these parts being damaged, mislaid orcontaminated. A new balancing procedure after exchange of an accessorypart is not necessary. Instead, the balancing procedure can be carriedout once for a defined microscope and for a defined set of accessoryparts. No automatic balancing devices of any kind are required anylonger. In this way, the stand as a whole can be made lighter, smallerand less expensive.

In some circumstances, the accessory parts for the microscope take up arelatively large amount of space, so that it can be difficult toaccommodate them at the end of the parallelogram linkage in thereceiving device. In this case, a receiving device for accessory partsof the microscope and for additional weights can be provided on the basepart. For each accessory part in this case, an equally heavy additionalweight is provided which, if it is made of solid metal for example,obviously takes up a much smaller volume than the accessory part. If therelatively large-volume accessory part is not needed, it can beaccommodated in the receiving device on the base part, where there issufficient space. In its place, the substantially smaller additionalweight is then arranged in the receiving device at the outer end of theparallelogram linkage near the microscope.

The invention can be used on all stands in which the microscope isarranged on a substantially horizontal parallelogram linkage.“Substantially horizontal” is intended to signify only that the standpart in question is not a substantially vertical stand part, which ismore or less vertical above a foot part, for example, but instead an armwhich extends to the side of the foot part or base part and at whose endthe microscope is arranged. The parallelogram arm could for example bearranged on a vertical column or on a horizontal double-hinge arm whichpermits coverage of the XY horizontal surface.

A particularly advantageous microscope system in which the parallelogramlinkage forms a first parallelogram linkage is characterized in that thestand also has:

a second substantially vertical parallelogram linkage with twosubstantially vertical bars and two substantially horizontal bars, ofwhich one of the substantially vertical bars is mounted on the base partso as to be able to pivot about a pivot axle,

a third substantially vertical parallelogram linkage whose first lowerhinge on the pivot axle of one of the substantially vertical bars of thesecond parallelogram linkage is connected to the base part, and whosesecond lower hinge is likewise connected to the base part and isconnected via its upper bar to the first parallelogram linkage,

where a substantially horizontal bar of the first parallelogram linkageis a continuation of the upper substantially horizontal bar of thesecond parallelogram linkage,

where the second lower hinge of the third parallelogram linkage isarranged higher than the first, the connection line between first andsecond hinge forms with the horizontal an angle of approximately 30° to60°, and the upper bar of the third parallelogram linkage forms thesecond further bar of the first parallelogram linkage.

In the already known microscope system, the first parallelogram linkageand the third parallelogram linkage are connected via a lever with twobranches which between them enclose an angle of 90°. The lower branch isalways held horizontal, and the upper branch is always held vertical.This provides a very great range of pivoting for the first parallelogramlinkage and consequently for the microscope arranged thereon. However,in the normal position, when the first parallelogram forms a rectangle,said first parallelogram is horizontal, with the result that theoperating surgeon can strike his head on it. For this reason, in theprior art, it is necessary for the substantially horizontal bars to bearranged high up or for them to have a curvature away from the operatingsite. In the microscope system according to the invention, this is notnecessary if provision is made that the second lower hinge of the thirdparallelogram linkage is arranged higher than the first, and that theconnection line between the first and second hinges forms with thehorizontal an angle of approximately 30° to 60°, and that the upper barof the third parallelogram linkage forms the second further bar of thefirst parallelogram linkage.

In this case, that bar of the first parallelogram linkage which issituated near the second and third parallelogram linkages is notvertical, but instead at an angle of approximately 30° to 60°,preferably 45°, so that in this normal position the first parallelogramlinkage is directed obliquely upwards and the operating surgeon has roomto stand below it.

After all the necessary accessory parts and the corresponding additionalweights are arranged in the receiving device on the first parallelogramlinkage or on the microscope, this microscope system can beequilibrated. This is expediently done by weights which can be arrangedon the parallelogram linkages, in particular on the second parallelogramlinkage. This balancing can be carried out once by a technician or by atheatre nurse for a given system, and it can be retained as long as theadditional devices for the microscope are not replaced by others.

Electrically or pneumatically releasable brakes are expediently arrangedon hinges and/or the pivot axle. These brakes are released only if thestand is to be adjusted, that is to say if the microscope is to be movedto another position.

A particularly expedient configuration is characterized in that the barsof the parallelogram linkages are pipes which are held in bushings whichform parts of the hinges and/or of the pivot axle. The hinge axlesand/or the pivot axle can be arranged in the bushings outside thelongitudinal axis of the pipes. To create more space for the operatingsurgeon, at least one bar of the parallelogram linkage can be curved inthe direction away from the operating site.

The base part will expediently rest on the floor and can be provided ina manner known per se with lockable castors. However, it could also bearranged, for example, on the wall or on the ceiling of the operatingtheatre. The base part expediently has a foot part and a column which ispivotable about a vertical axle and on which the further parts of thestand are then arranged.

However, the main feature of the invention is that, when the stand isswiveled, the angle at which the microscope and the receiving device forthe accessory parts are oriented does not change. If the total weight ofthe microscope and of the accessory parts which are arranged on themicroscope or on/in the receiving device does not change, the balance ismaintained.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be described below on the basis of advantageousembodiments and with reference to the attached drawings in which:

FIG. 1 shows the microscope system according to the invention in adiagrammatic view from the side;

FIG. 2 is a detail of the encircled portion of FIG. 1 in cross section;

FIG. 3 is a detail of another embodiment corresponding to the encircledportion of FIG. 1;

FIG. 4 is another embodiment of the microscope system according to theinvention in a diagrammatic view from the side;

FIG. 5 is a detail of another embodiment corresponding to the lower lefthand side of the parallelogram linkage of FIGS. 1 and 4; and

FIGS. 6a and 6 b are details of the receiving device for accessory partsfor the microscope.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 1, a column 3 which is pivotable about a vertical axisis arranged on a foot part 1 via a hinge 2. A parallelogram linkage,which is referred to below as the “second parallelogram linkage”, isarranged on this column 3 so as to pivot about a horizontal pivot axle4. This second parallelogram linkage has vertical bars 5, 6 andsubstantially horizontal bars 7, 8 which are each connected by hinges 9.Balancing weights 10 with which the stand can be equilibrated arearranged on the lower left hinge 9. The hinge connection which connectsbars 6 and 7 could be an axle which is fixed to bar 7 or weight 10. Tothis axle bar 6 is rotatably fixed. Also the weight 10 can be fixed tobar 7. Weight 10 could e.g. be fixed to bar 7 with a screw threadconnection in order that it can be changed. Instead of providing suchweights 10 only at one position, it is also possible for such weights tobe provided at another position, for example weights 11 on the lower bar7, as is shown in FIG. 1. Weight 11 can, as indicated in FIG. 1, bemerely suspended from bushing 21 by a wire or a bar. It also could befixed by a screw connection to bushing 21 or bar 7. Movable weightscould also be arranged on the bar 6 or 7.

The upper bar 8 of the second parallelogram linkage 5 to 9 is continuedto the right and here forms part of a first parallelogram linkage which,in addition to said bar 8, has a substantially horizontal bar 12 and twofurther bars 13, 14. The bars 8, 12, 13, 14 are likewise connected byhinges 9 to form a parallelogram linkage. The bar 13 here forms a partof a third parallelogram linkage which, in addition to the bar 13, has apart of the bar 5 of the second parallelogram linkage, as far as thepivot axle 4, a further substantially vertical bar 15 which is mountedat 16 on the base part 1, 2, 3, and which forms the connection betweenpivot axle 4 and hinge 16. The connection line between pivot axle 4 andhinge 16 is in this case at said angle of approximately 30° to 60°, herein particular 45° (as shown in FIG. 1), to the horizontal, by whichmeans the corresponding orientation of the bar 13 is fixed.

The mounting device 17 for the microscope is connected to the furtherbar 14 which, even upon swiveling of the parallelogram linkage, remainsparallel to the bar 13 and thus does not change its orientation. Areceiving device 18 for accessory parts of the microscope is alsoconnected to this first further bar 14 of the first parallelogramlinkage. This receiving device 18 can accommodate not only accessoryparts (not shown in the figure) of the microscope, but also additionalweights whose mass corresponds to the mass of accessory parts which,when not in use, can be accommodated in a receiving device 19 on thefoot 1 of the microscope. The microscope itself is indicated at 20.

As shown in FIG. 2 which is an enlarged cross section view of theencircled portion of FIG. 1, bars 6 and 8 are hollow pipes which areheld in bushings 21 which form part of the hinges 9. These hingescomprise two bushings 21 and an axle 22 which connects the two bushingsin a rotational manner.

As can be seen in FIG. 3, the relative rotation of the two bushings canbe blocked by a brake which contains a solenoid or pneumatic cylinder 23which can press a plunger 24 against axle 22 which in this case is fixedto upper bushing 21 and can rotate within lower bushing 21.

As can also be seen in FIG. 3, the axle 22 can be arranged outside thelongitudinal axis 25 of the bar or pipe 8. This, of course, can be thecase also for other hinge axles or pivot axles.

In FIG. 5, details of another embodiment are shown in which weight 11 isintegral with bar 7, this integral unit connecting the lower hinge 9 ofbar 5 with weight 10.

Details of the receiving device 18 are shown in FIGS. 6a and 6 b. Thereceiving device in this embodiment comprises a tray 27 which is affixedto bar 14 and on which accessory parts can be placed. These parts can bereceived also by holders which e.g. are fixed to bar 14 as shown in FIG.6b. the receiving device further comprises a cover 26 which is pivotablyconnected to hinge 9.

Receiving device 18 remains horizontally positioned. Pivot axles 4 and16 are arranged under a fixed angle with respect to the horizontal, inthe figure under 45. Because 5, 4, 16, 15, 9, 13, 9 is a parallelogramlinkage, also part 13 will be arranged under 45 with respect to thehorizontal. Because 13, 9, 12, 9, 14, 9, 8 is also a parallelogramlinkage, part 14 will be always parallel to part 13 and thus also alwaysoriented under 45 with respect to the horizontal. Therefore, device 18is always horizontally aligned if as shown in FIG. 1 if it is alignedunder 45 with respect to part 14.

The rotational moment (torque) which is exerted by the microscope 20,the receiving device 18 and the weights of the bars 8, 12, 13, 14 andthe other parts of the first horizontal parallelogram linkage, can beperfectly compensated by the counterweight 10 If the bar 15 is heldfixed. If rotation of the bar 5 about the pivot axle 4 is permitted, itis possible that the stand will fall into an extreme position. If thecentre of gravity of the whole system is above the axle 4, the systemstretches fully, and if it lies under the axle 4, the bar 5 moves untilthe angle a 90° is reached. By means of the further weight 11, the standcan now be compensated so that the centre of gravity lies in the pivotaxle 4 and thus the microscope weight is compensated in each positionirrespective of the angles α and β.

The weights 10 and 11 can be positioned at different places. Thus, theweight 10 can be secured at any point on the bar 6. The weight 10 canalso be secured on the bar 7 or on the continuation thereof, in whichcase the weight 10 must then be made bigger or smaller to compensate themoments. The weight 11 can also be moved on the bar 7 or can be arrangedon the bar 5 under the pivot axle 4 or on a downward continuation of thebar 5. In the latter case, a variation of the weight 11 is likewisenecessary according to the distance from the pivot axle 4. The weights10, 11 can also be combined partially or completely in one weight. Theweights or parts thereof can also be arranged inside the bars 5, 6 or 7.In this way it is possible to keep the width of the stand as small aspossible and to minimize the excursion of counterweights, by which meansthe theatre sister's access to the operating site is optimized.

On at least two hinges 9 of the stand, brakes are arranged which can beopened or closed by electrical actuation. One such brake 23, 24 is shownin FIG. 3. If the microscope 20 is to be spatially moved, all brakes arereleased by pressing a button on a hand piece of the operatingmicroscope, as a result of which the microscope can be brought withminimal effort into any position inside the range of movement of themicroscope 20. These brakes are preferably arranged in the hinge 9 inthe compensating weight 10 and in the pivot axle 4, so that the weightof the brakes either has no influence or contributes to the weightcompensation. The transformer for current supply is also preferablyarranged at the hinge 9 at the weight 10.

The weights 10 and 11 are chosen such that, at a maximum weight of theoperating microscope, the stand is fully compensated. The weights 10 and11 are then fixed.

On the mounting device 17 for the microscope there is a receiving device18, on or in which the accessory parts of the microscope can bearranged. This receiving device can either be a box or a holder withannular recesses similar to the fastening possibilities on the operatingmicroscope, or a combination of the two. If, for example, the physicianchanges from a cranial operation, in which the assistant stands at theside of the operating surgeon, to a spinal column operation in which theassistant sits opposite the operating surgeon on the other side of theoperating table, in order to prepare for the operation the theatre nurseonly needs to remove the co-observation tube from the operatingmicroscope and place it in the receiving device 18 on the mountingdevice 17 for the microscope. Conversely, she will remove a secondviewing piece from the receiving device and will arrange it on theoperating microscope 20 opposite the operating surgeon. In this way, thestand remains completely weight-compensated, without weights having tobe moved or operating buttons having to be actuated. There is also nolonger any need for the theatre nurse to carry an expensive opticalelement through the operating theatre or to a storage location and thusrun the risk of the optical element being damaged.

If the overall configuration of the microscope has to be changed fromtime to time, for example by attachment of a lighter video camera, thestand has to be re-compensated only in these cases. This compensationshould preferably be carried out by a service engineer or a hospitaltechnician. To do this, weight elements are preferably either removedfrom or fitted on the compensating weights 10 and 11, or other weightelements are added or removed in the area of the mounting device 17 forthe microscope or in the area of the receiving device 18. For thispurpose, a set of weights is supplied with the operation system. Inaddition, the brake control is configured in such a way that the brakesin the pivot axle 4 and in the hinge 16 can be opened separately. For atechnician, it is then a very simple matter to re-establish a perfectweight compensation with the new microscope weight.

For fine adjustment at the time of installation or after a subsequentchange in the supporting weight, smaller weights can be arranged on thebars 5, 6 or 7, which smaller weights are moved and then fixed. It isalso possible to design the weight 10 or 11 or both of them so that theyare slightly movable, in order thereby to carry out fine adjustment.

The bars 5, 6, 7, 8, 12, 13, 14, 15 are preferably designed as pipes,with different cross-sectional shapes being possible. The pipes can beconnected to one another by bushings 21 (FIG. 3) in which the hinges forthe movement are located. In this case, it is advantageous if the hingeaxes are located outside the pipes. If in fact the pipe 8 is arrangedabove the hinges, height is gained for the surgeon when he is operatingunderneath the bars of the first parallelogram linkage. To gain stillfurther height, it is also possible to provide the bar 8 with anupwardly directed curvature in the area in which the surgeon can standduring the operation. Such an embodiment is shown in FIG. 4.

As has already been described, the size of the receiving device 18 mustbe such as to be able to receive the accessory parts of the operatingmicroscope 20. If many parts are to be changed from one operation to thenext, it is also conceivable to accommodate these parts elsewhere, forexample in a compartment 19 at the foot 1 of the stand, and, in theirplace, to remove different weights 1 from this compartment 19 andarrange them in the receiving device 18. Since these weights can have amuch smaller volume, the receiving device 18 can turn out considerablysmaller.

Where reference is made to bars of the parallelogram linkages, thismeans the parallelogram sides. One of these parallelogram sides betweenpivot axle 4 and hinge 16 is not of course such a bar or does not needto be such a bar. This is also the case for other so-called bars, inparticular the bar 14. Instead of providing a bar 14, the bars 8 and 12could be connected with hinges 9 directly to the receiving device 18.

What is claimed:
 1. Microsurgical microscope system with a stand andwith a microscope arranged thereon, in which system the stand has a basepart and a substantially horizontal parallelogram linkage with twosubstantially horizontal bars and outer and inner further barsconnecting the horizontal bars, of which the outer further bar isconnected to a mounting device for the microscope, characterized in thatthe outer further bar also has a receiving device connected to it foraccessory parts of the microscope, said mounting device, microscope,receiving device, and accessory parts having a total weight, said standbeing balanced to support said total weight at said outer further barand said total weight at said outer further bar remaining constantwhether said accessory parts are attached to said microscope or locatedon said receiving device.
 2. Microscope system according to claim 1,characterized in that a second receiving device for accessory parts ofthe microscope and additional weights is provided on the base part. 3.Microscope system according to claim 1, in which the parallelogramlinkage forms a first parallelogram linkage, characterized in that thestand also has: a second substantially vertical parallelogram linkagewith two substantially vertical bars and two substantially horizontalbars, of which one of the substantially vertical bars is mounted on thebase part so as to be able to pivot about a pivot axle, a thirdsubstantially vertical parallelogram linkage whose first lower hinge onthe pivot axle of one of the substantially vertical bars of the secondparallelogram linkage is connected to the base part, and whose secondlower hinge is likewise connected to the base part and is connected viaits upper bar to the first parallelogram linkage, where a substantiallyhorizontal bar of the first parallelogram linkage is a continuation ofthe upper substantially horizontal bar of the second parallelogramlinkage, where the second lower hinge of the third parallelogram linkageis arranged higher than the first, the connection line between first andsecond hinges forms with the horizontal an angle of approximately 30 to60°, and the upper bar of the third parallelogram linkage forms theinner further bar of the first parallelogram linkage.
 4. Microscopesystem according to claim 3, characterized in that the connection linebetween first and second hinges forms with the horizontal an angle ofapproximately 45°.
 5. Microscope system according to claim 3,characterized in that electrically or pneumatically releasable brakesare arranged on hinges.
 6. Microscope system according to claim 3,characterized in that it has weights which are arranged on theparallelogram linkages.
 7. Microscope system according to claim 3,characterized in that the bars are pipes which are held in bushingswhich form parts of the hinges.
 8. Microscope system according to claim7, characterized in that the hinge axles are arranged in the bushingsoutside the longitudinal axis of the pipes.
 9. Microscope systemaccording to claim 3, characterized in that an electrically orpneumatically releasable brake is arranged on the pivot axle. 10.Microscope system according to claim 3, characterized in that it hasweights which are arranged on the second parallelogram linkage. 11.Microscope system according to claim 3, characterized in that at leastone bar is a pipe which is held in a bushing which forms a part of thepivot axle.
 12. Microscope system according to claim 11, characterizedin that the pivot axle is arranged in the bushing outside thelongitudinal axis of the pipe.
 13. Microscope system according to claim1, characterized in that at least one bar of the parallelogram linkagesis curved in the direction away from the operating site.
 14. Microscopesystem according to claim 1, characterized in that the base part has afoot part and a column which is pivotable about a vertical axle. 15.Microscope system according to claim 1, comprising weights receivable onsaid receiving device to compensate for the weight of one or more ofsaid accessory parts removed from said microscope and said receivingdevice.